Isolation and identification of spotted fever group Rickettsiae BJ-93 strain

One strain of rickettsiae was isolated from Dermacentor sinicus collected from Changping county in Beijing city in 1993 by using embryonated hen's eggs and proved to be the member of spotted fever group(SFG)rickettsiae. It was named as BJ-93 after the name of the place and the year which it was isolated. The isolate was compared with known species and strains of SFGR by micro-immunofluorescence assay, DNA polymerase chain reaction, DNA polymerase chain reaction followed by restriction endonuclease fragment length polymorphism analysis, sodium dodecylsulfate-polyacrylamide gel electrophoresis, protein immunoblotting with polyclonal and monoclonal antibodies, dot immunobinding assay. The results demonstrated that BJ-93 strain was antigenically and genotypically identical to BJ-90 strain, and genotypically identical and antigenically related to R. sibirica 246 strain but its profile was different.